Based on the slowing of the Sun’s “Great Conveyor Belt”, he predicted that

“The slowdown we see now means that Solar Cycle 25, peaking around the year 2022, could be one of the weakest in centuries.”
He is very likely to have got the year wrong in that Solar Cycle 25 is unlikely to start until 2025.

Livingston and Penn provided the first hard estimate of Solar Cycle 25 amplitude based on a physical model. That estimate is 7, which would make it the smallest solar cycle for over 300 years.
This is figure 2 from their paper:

Livingston and Penn have been tracking the decline in sunspot magnetic field, predicting that sunspots will disappear when the umbral magnetic field strength falls below 1,500 gauss, as per this figure from their 2010 paper:

Dr Svalgaard has updated of the progression of that decline on his research page at:

http://www.leif.org/research/Livingston%20and%20Penn.png

With data updated to year end 2011, the line of best fit on Dr Svalgaard’s figure of Umbral Magnetic Field now intersects the 1,500 guass sunspot cutoff in 2030:

Using the Livingston and Penn Solar Cycle 25 amplitude estimate, this is what the solar cycle record is projected to look like: